Connecticut Tax Deduction Checklist — 2026
Maximize your tax savings with our comprehensive checklist of tax deductions available to self-employed individuals.
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Quick Connecticut Tax Estimate
Based on Connecticut's tax rates for 2026. Enter your details for a personalized calculation.
State Tax on $80K Profit
$1,651.17
SE Tax
$11,303.64
Effective Rate
22.2%
Marginal Rate
12%
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Connecticut Tax Information
State Income TaxYes
Top Marginal Rate7%
Sales Tax0%
LLC Filing Fee$0
Annual Report Fee$None
Standard DeductionN/A
Self-employed pay both federal and Connecticut state tax.
Connecticut Income Tax Brackets (2026)
| Tax Rate | From | To |
|---|---|---|
| 2% | $0 | $10,000 |
| 4.5% | $10,000 | $50,000 |
| 5.5% | $50,000 | $100,000 |
| 6% | $100,000 | $200,000 |
| 6.5% | $200,000 | $250,000 |
| 6.9% | $250,000 | $500,000 |
| 7% | $500,000 | No limit |
Connecticut Quarterly Tax Deadlines
Q1
Apr 15
Q2
Jun 16
Q3
Sep 15
Q4
Jan 15
Frequently Asked Questions
What is the biggest deduction for self-employed in Connecticut?
The self-employment tax deduction (50% of SE tax), health insurance premiums, and retirement contributions are typically the largest. The QBI deduction (20% of qualified business income) can also be substantial.
Can I deduct my home office in Connecticut?
Yes, if used regularly and exclusively for business. Simplified method: $5/sq ft up to 300 sq ft (max $1,500). Regular method: actual expenses prorated by square footage percentage.
What vehicle expenses can I deduct in Connecticut?
Standard mileage rate: $0.70/mile for 2026. Or actual expenses (gas, insurance, repairs, depreciation) prorated by business use %. Track all business miles with a log or app.
Are health insurance premiums deductible in Connecticut?
Yes. Self-employed individuals can deduct 100% of health, dental, and long-term care insurance premiums for themselves, spouse, and dependents. This is an above-the-line deduction.
What can't I deduct as self-employed in Connecticut?
Non-deductible: personal expenses, commuting to your regular workplace, clothing wearable outside work (unless uniforms), entertainment, political contributions, and fines/penalties.
Disclaimer:This calculator provides estimates for informational purposes only. It does not constitute tax advice, financial advice, or legal advice. Tax laws change frequently and vary by individual circumstances. Results may not reflect your actual tax liability. Always consult a qualified CPA, tax professional, or financial advisor before making tax decisions. For official tax information, visit IRS.gov.